I received my MBA 2012 only two days ago, and last night I found there is a small gap btween the bottom case and upper panel on the left hand side near the trackpad. I suppose it may be the defective battery swelling making the case warped. It is my first Macbook product, I'm really disappointed. 🙁 Im just wondering is it very common for Macbook? Should I ask for a new MBA replacement or just the battery? Coz my one is customized with 8G ram, and it took me almost one week to get after I placed my order. Am I lucky or unlucky with this experience?😡